Methods for detection of Helicobacter pylori from stool sample: current options and developments.

Accurate detection of Helicobacter pylori infection and determination of antibiotics have significant meaning in clinical practice. The detection methods can be categorized into two types, invasive and non-invasive, but nowadays we use the urease breath test most frequently which is non-invasive. However, many developing countries cannot meet the requirements for having specialized equipment and they lack trained personnel. Also, for the children, it is difficult to make them cooperate for the test. Methods that detect Helicobacter pylori from stool sample can be a promising alternative for detection used in children and mass screening. Stool antigen tests have several advantages such as rapidity, simplicity, and cheapness, though their results may be influenced by the heterogenicity of antigens, the nature of biochemical techniques, and the amount of antigen presented in the stool. PCR-based methods can specifically detect Helicobacter pylori infection and antibiotic resistance by targeting specific gene sequence, but they also are limited by the requirements of facilities and experts, the existence of inhibitory substance, and interference from the dead bacteria. Some novel methods also deserve our attention. Here we summarized the results of researches about methods using stool sample and we hope our work can help clinicians choose the appropriate test in clinical practice.

Neoteric advancements in TB diagnostics and its future frame.

Tuberculosis (TB) is one of the major infectious disease that causes threat to human health and leads to death in most of the cases. Mycobacterium tuberculosis is the causative agent that can affect both pulmonary and extra pulmonary regions of the body. This infection can be presented either as an active or latent form in the patients. Although this disease has been declared curable and preventable by WHO, it still holds its position as a global emergency. Over the past decade many hurdles such as low immunity, co-infections like HIV, autoimmune disorders, poverty, malnutrition and emerging trends in drug resistance patterns are hindering the eradication of this infection. However, many programmes have been launched by WHO with involvement of governments at various level to put a full stop over the disease. Under the Revised National Tuberculosis Control Programme (RNTCP) which was recently renamed as National Tuberculosis Elimination Programme (NTEP), the major focus is on eliminating tuberculosis by the year 2025. The main aim of the programme is to identify feasible quality testing, evaluate through NIKSHYA poshak yozana, restrict through BCG vaccination and assemble with public awareness to eradicate MTB. Numerous novel diagnostic techniques and molecular tools have been developed to elucidate and differentiate report of various suspected and active tuberculosis patients. However, improvements are still required to cut short the duration of the overall process ranging from screening of patients to their successful treatment.

Assessment of bacterial viability: a comprehensive review on recent advances and challenges.

Assessing bacterial contamination in environmental samples is critical in determining threats to public health. The classical methods are time-consuming and only recognize species that grow easily on culture media. Viable but non-culturable (VBNC) bacteria are a possible threat that may resuscitate and cause infections. Recent dye-based screening techniques employ nucleic acid dyes such as ethidium monoazide (EMA) and propidium monoazide (PMA), along with many fluorescent dyes, which are an effective alternative for viability assessment. The measurement of cellular metabolism, heat flow and ATP production has also been widely applied in detection approaches. In addition, RNA-based detection methods, including nucleic acid sequence-based amplification (NASBA), have been applied for bacterial pathogen determination. Stable isotope probing using 13C, 15 N and 18O, which are mobilized by microbes, can also be used for effective viability assessment. Future detection tools, such as microarrays, BioNEMS and BioMEMS, which are currently being validated, might offer better microbial viability detection.

Comparative evaluation of the identification of rapidly growing non-tuberculous mycobacteria by mass spectrometry (MALDI-TOF MS), GenoType Mycobacterium CM/AS assay and partial sequencing of the rpoBeta gene with phylogenetic analysis as a reference method / Evaluación comparativa de la identificación de micobacterias no tuberculosas de crecimiento rápido mediante espectrometría de masas (MALDI-TOF MS), GenoType(R) Mycobacterium CM/AS assay y la secuenciación parcial del gen rpoBeta con análisis filogenético como método de referencia

Introduction: The American Thoracic Society and the Infectious Diseases Society of America recommend that clinically significant non-tuberculous mycobacteria (NTM) should be identified to the species level in order to determine their clinical significance. The aim of this study was to evaluate identification of rapidly growing NTM (RGM) isolated from clinical samples by using MALDI-TOF MS and a commercial molecular system. The results were compared with identification using a reference method. Methods: We included 46 clinical isolates of RGM and identified them using the commercial molecular system GenoType(R) CM/AS (Hain, Lifescience, Germany), MALDI-TOF MS (Bruker) and, as reference method, partial rpoBeta gene sequencing followed by BLAST and phylogenetic analysis with the 1093 sequences available in the GeneBank. Results: The degree of agreement between GenoType(R) and MALDI-TOF MS and the reference method, partial rpoBeta sequencing, was 27/43 (62.8%) and 38/43 cases (88.3%) respectively. For all the samples correctly classified by GenoType(R), we obtained the same result with MALDI-TOF MS (27/27). However, MALDI-TOF MS also correctly identified 68.75% (11/16) of the samples that GenoType(R) had misclassified (p = 0.005). Conclusions: MALDI-TOF MS classified significantly better than GenoType(R). When a MALDI-TOF MS score >1.85 was achieved, MALDI-TOF MS and partial rpoBeta gene sequencing were equivalent. GenoType(R) was not able to distinguish between species belonging to the M. fortuitum complex. MALDI-TOF MS methodology is simple, rapid and associated with lower consumable costs than GenoType(R). The partial rpoBeta sequencing methods with BLAST and phylogenetic analysis were not able to identify some RGM unequivocally. Therefore, sequencing of additional regions would be indicated in these cases

Introducción: La American Thoracic Society y la Infectious Diseases Society of America recomiendan que las micobacterias no tuberculosas (MNT) clínicamente relevantes sean identificadas a nivel de especie para determinar su significado clínico. El propósito de este estudio fue a partir de MNT de crecimiento rápido (MCR) aisladas en muestras clínicas, evaluar su identificación mediante MALDI-TOF MS y un método molecular comercial, comparando estos resultados con la identificación obtenida usando un método de referencia. Métodos: Se incluyeron 46 aislados clínicos de MCR. Estos aislados se identificaron mediante el método molecular comercial GenoType(R) Mycobacterium CM/AS (Hain, Lifescience, Alemania), MALDI-TOF MS (Bruker) y, como método de referencia, la secuenciación parcial del gen rpoBeta seguido de BLAST y análisis filogenético. Para el análisis filogenético se utilizaron 1.093 secuencias disponibles en el GeneBank. Resultados: Entre GenoType(R) o MALDI-TOF MS, la concordancia respecto al método de referencia, secuenciación parcial de rpoB, fue 27/43 (62,8%) y 38/43 casos (88,3%), respectivamente. En todas las muestras que GenoType(R) clasificó correctamente con MALDI-TOF MS se obtuvo el mismo resultado (27/27). Pero además MALDI-TOF MS identificó bien 68,75% (11/16) de las muestras que GenoType(R) no clasificó correctamente (p = 0,005). Conclusiones: MALDI-TOF MS clasificó significativamente mejor que GenoType(R). Cuando MALDI-TOF MS alcanzó una puntuación >1,85, MALDI-TOF y la secuenciación parcial del gen rpoβ fueron equivalentes. GenoType(R) no distinguió dentro del M. fortuitum complex. La metodología MALDI-TOF MS es simple, rápida y se asocia a un menor coste de consumibles que GenoType(R). La secuenciación parcial del gen rpoBeta con BLAST y análisis filogenético no lograron identificar de manera inequívoca algunas MCR. Para estas MCR estaría indicado la secuenciación de regiones adicionales

[The future of automation in bacteriology]. / Automatisation en bactériologie : quel avenir ? Un exemple concret dans le cadre d'une consolidation de laboratoires universitaires.

Bacteriology remained essentially manual for many years. After a partial automation for blood cultures, identifications and sensitivity testing, new technological developments including robotisation and digital pictures made it possible to open new ways. In the context of economic pression and need to increase the quality, automation offers multiple advantages concerning increase of productivity, standardization, traceability and decreasing of the delay to obtain the results. Moreover the use of digitalized pictures opens the way to tele-bacteriology, particularly useful when considering the merging of hospital laboratories because it makes it possible to geographically dissociate strict manipulation from the validation of the results and from the consultant activity of the microbiologist. The choice criteria of the equipment are detailed as well as the experience of the LHUB-ULB bacteriological laboratory which was automated at the time of merging of the Brussels public hospital laboratories and developed a conclusive experience of tele-bacteriology for the peripheral lab.

Need for Laboratory Ecosystems To Unravel the Structures and Functions of Soil Microbial Communities Mediated by Chemistry.

The chemistry underpinning microbial interactions provides an integrative framework for linking the activities of individual microbes, microbial communities, plants, and their environments. Currently, we know very little about the functions of genes and metabolites within these communities because genome annotations and functions are derived from the minority of microbes that have been propagated in the laboratory. Yet the diversity, complexity, inaccessibility, and irreproducibility of native microbial consortia limit our ability to interpret chemical signaling and map metabolic networks. In this perspective, we contend that standardized laboratory ecosystems are needed to dissect the chemistry of soil microbiomes. We argue that dissemination and application of standardized laboratory ecosystems will be transformative for the field, much like how model organisms have played critical roles in advancing biochemistry and molecular and cellular biology. Community consensus on fabricated ecosystems ("EcoFABs") along with protocols and data standards will integrate efforts and enable rapid improvements in our understanding of the biochemical ecology of microbial communities.

Culturing the human microbiota and culturomics.

The gut microbiota has an important role in the maintenance of human health and in disease pathogenesis. This importance was realized through the advent of omics technologies and their application to improve our knowledge of the gut microbial ecosystem. In particular, the use of metagenomics has revealed the diversity of the gut microbiota, but it has also highlighted that the majority of bacteria in the gut remain uncultured. Culturomics was developed to culture and identify unknown bacteria that inhabit the human gut as a part of the rebirth of culture techniques in microbiology. Consisting of multiple culture conditions combined with the rapid identification of bacteria, the culturomic approach has enabled the culture of hundreds of new microorganisms that are associated with humans, providing exciting new perspectives on host-bacteria relationships. In this Review, we discuss why and how culturomics was developed. We describe how culturomics has extended our understanding of bacterial diversity and then explore how culturomics can be applied to the study of the human microbiota and the potential implications for human health.

Emerging Technologies for Molecular Diagnosis of Sepsis.

Rapid and accurate profiling of infection-causing pathogens remains a significant challenge in modern health care. Despite advances in molecular diagnostic techniques, blood culture analysis remains the gold standard for diagnosing sepsis. However, this method is too slow and cumbersome to significantly influence the initial management of patients. The swift initiation of precise and targeted antibiotic therapies depends on the ability of a sepsis diagnostic test to capture clinically relevant organisms along with antimicrobial resistance within 1 to 3 h. The administration of appropriate, narrow-spectrum antibiotics demands that such a test be extremely sensitive with a high negative predictive value. In addition, it should utilize small sample volumes and detect polymicrobial infections and contaminants. All of this must be accomplished with a platform that is easily integrated into the clinical workflow. In this review, we outline the limitations of routine blood culture testing and discuss how emerging sepsis technologies are converging on the characteristics of the ideal sepsis diagnostic test. We include seven molecular technologies that have been validated on clinical blood specimens or mock samples using human blood. In addition, we discuss advances in machine learning technologies that use electronic medical record data to provide contextual evaluation support for clinical decision-making.

Recent advances in the microbiological diagnosis of bloodstream infections.

Rapid identification (ID) and antimicrobial susceptibility testing (AST) of the causative agent(s) of bloodstream infections (BSIs) are essential for the prompt administration of an effective antimicrobial therapy, which can result in clinical and financial benefits. Immediately after blood sampling, empirical antimicrobial therapy, chosen on clinical and epidemiological data, is administered. When ID and AST results are available, the clinician decides whether to continue or streamline the antimicrobial therapy, based on the results of the in vitro antimicrobial susceptibility profile of the pathogen. The aim of the present study is to review and discuss the experimental data, advantages, and drawbacks of recently developed technological advances of culture-based and molecular methods for the diagnosis of BSI (including mass spectrometry, magnetic resonance, PCR-based methods, direct inoculation methods, and peptide nucleic acid fluorescence in situ hybridization), the understanding of which could provide new perspectives to improve and fasten the diagnosis and treatment of septic patients. Although blood culture remains the gold standard to diagnose BSIs, newly developed methods can significantly shorten the turnaround time of reliable microbial ID and AST, thus substantially improving the diagnostic yield.

Waltzing around Sacred Cows on the Way to the Future.

Our mostly manual, agar-based clinical microbiology laboratory is slowly but steadily being redefined by automation and innovation. Ironically, the oldest test, the Gram stain test, is still manually read and interpreted by trained personnel. In a proof-of-concept study, Smith et al. (J. Clin. Microbiol. 56:e01521-17, 2018, https://doi.org/10.1128/JCM.01521-17) used computer imaging with a deep convolutional neural network to examine and interpret Gram-stained slides from positive blood culture bottles. In light of the shortage of medical technologists/microbiologists and the need for results from positive blood culture bottles 24/7, this paper paves the way for the next innovations for the clinical microbiology laboratory of the future.

Emerging Microtechnologies and Automated Systems for Rapid Bacterial Identification and Antibiotic Susceptibility Testing.

Rapid bacterial identification (ID) and antibiotic susceptibility testing (AST) are in great demand due to the rise of drug-resistant bacteria. Conventional culture-based AST methods suffer from a long turnaround time. By necessity, physicians often have to treat patients empirically with antibiotics, which has led to an inappropriate use of antibiotics, an elevated mortality rate and healthcare costs, and antibiotic resistance. Recent advances in miniaturization and automation provide promising solutions for rapid bacterial ID/AST profiling, which will potentially make a significant impact in the clinical management of infectious diseases and antibiotic stewardship in the coming years. In this review, we summarize and analyze representative emerging micro- and nanotechnologies, as well as automated systems for bacterial ID/AST, including both phenotypic (e.g., microfluidic-based bacterial culture, and digital imaging of single cells) and molecular (e.g., multiplex PCR, hybridization probes, nanoparticles, synthetic biology tools, mass spectrometry, and sequencing technologies) methods. We also discuss representative point-of-care (POC) systems that integrate sample processing, fluid handling, and detection for rapid bacterial ID/AST. Finally, we highlight major remaining challenges and discuss potential future endeavors toward improving clinical outcomes with rapid bacterial ID/AST technologies.

The value of cultures to modern microbiology.

Since the late nineteenth century, pure cultures have been regarded as the cornerstone of bacteriology. However, not all bacteria will multiply sufficiently to produce visible colonies on solid media; some cells will produce micro-colonies that are invisible to the naked eye. Moreover, the proportion of culturable cells that produce visible growth will vary according to the species and the state of the cells-are they actively growing or comparatively inactive? The latter have a poorer rate of recovery in terms of cultivability. It is unclear whether or not an individual colony is always derived from a single cell; it is possible that organisms in close proximity to each other may multiply and come together to produce single colonies. Then, the resultant growth will most certainly be derived from more than one initial cell. Although it is generally assumed that streaking and re-streaking on fresh media will purify any culture, there is evidence for microbial consortia interacting to form what appear to be single pure cultures. As so-called pure cultures underpin traditional microbiology, it is relevant to understand that the culture does not necessarily contain clones of identical bacteria, but that there may be variation in the genetic potential of the component cells, i.e. the cells are not homogeneous. Certainly, many bacteria change rapidly upon culturing, with some becoming bigger and less active. It is difficult to be sure if these changes reflect a loss or change of DNA or whether standard culturing methods select faster growing cells that are effectively not representative of the environment from which they were derived. These concepts are reviewed with an emphasis on bacterial fish pathogens.

New Technologies for Rapid Bacterial Identification and Antibiotic Resistance Profiling.

Conventional approaches to bacterial identification and drug susceptibility testing typically rely on culture-based approaches that take 2 to 7 days to return results. The long turnaround times contribute to the spread of infectious disease, negative patient outcomes, and the misuse of antibiotics that can contribute to antibiotic resistance. To provide new solutions enabling faster bacterial analysis, a variety of approaches are under development that leverage single-cell analysis, microfluidic concentration and detection strategies, and ultrasensitive readout mechanisms. This review discusses recent advances in this area and the potential of new technologies to enable more effective management of infectious disease.

Trends in Testing for Mycobacterium tuberculosis Complex From US Public Health Laboratories, 2009-2013.

OBJECTIVE: We investigated data from US public health laboratories funded through the Centers for Disease Control and Prevention's Tuberculosis Elimination and Laboratory Cooperative Agreement to document trends and challenges in meeting national objectives in tuberculosis (TB) laboratory diagnoses. METHODS: We examined data on workload and turnaround time from public health laboratories' progress reports during 2009-2013. We reviewed methodologies, laboratory roles, and progress toward rapid detection of Mycobacterium tuberculosis complex through nucleic acid amplification (NAA) testing. We compared selected data with TB surveillance reports to estimate public health laboratories' contribution to national diagnostic services. RESULTS: During the study period, culture and drug susceptibility tests decreased, but NAA testing increased. Public health laboratories achieved turnaround time benchmarks for drug susceptibility tests at lower levels than for acid-fast bacilli smear and identification from culture. NAA positivity in laboratories among surveillance-reported culture-positive TB cases increased from 26.6% (2355 of 8876) in 2009 to 40.0% (2948 of 7358) in 2013. Public health laboratories provided an estimated 50.9% (4285 of 8413 in 2010) to 57.2% (4210 of 7358 in 2013) of culture testing and 88.3% (6822 of 7727 in 2011) to 94.4% (6845 of 7250 in 2012) of drug susceptibility tests for all US TB cases. CONCLUSIONS: Public health laboratories contribute substantially to TB diagnoses in the United States. Although testing volumes mostly decreased, the increase in NAA testing indicates continued progress in rapid M tuberculosis complex detection.

CRISPR technologies for bacterial systems: Current achievements and future directions.

Throughout the decades of its history, the advances in bacteria-based bio-industries have coincided with great leaps in strain engineering technologies. Recently unveiled clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas) systems are now revolutionizing biotechnology as well as biology. Diverse technologies have been derived from CRISPR/Cas systems in bacteria, yet the applications unfortunately have not been actively employed in bacteria as extensively as in eukaryotic organisms. A recent trend of engineering less explored strains in industrial microbiology-metabolic engineering, synthetic biology, and other related disciplines-is demanding facile yet robust tools, and various CRISPR technologies have potential to cater to the demands. Here, we briefly review the science in CRISPR/Cas systems and the milestone inventions that enabled numerous CRISPR technologies. Next, we describe CRISPR/Cas-derived technologies for bacterial strain development, including genome editing and gene expression regulation applications. Then, other CRISPR technologies possessing great potential for industrial applications are described, including typing and tracking of bacterial strains, virome identification, vaccination of bacteria, and advanced antimicrobial approaches. For each application, we note our suggestions for additional improvements as well. In the same context, replication of CRISPR/Cas-based chromosome imaging technologies developed originally in eukaryotic systems is introduced with its potential impact on studying bacterial chromosomal dynamics. Also, the current patent status of CRISPR technologies is reviewed. Finally, we provide some insights to the future of CRISPR technologies for bacterial systems by proposing complementary techniques to be developed for the use of CRISPR technologies in even wider range of applications.

Recent and emerging innovations in Salmonella detection: a food and environmental perspective.

Salmonella is a diverse genus of Gram-negative bacilli and a major foodborne pathogen responsible for more than a million illnesses annually in the United States alone. Rapid, reliable detection and identification of this pathogen in food and environmental sources is key to safeguarding the food supply. Traditional microbiological culture techniques have been the 'gold standard' for State and Federal regulators. Unfortunately, the time to result is too long to effectively monitor foodstuffs, especially those with very short shelf lives. Advances in traditional microbiology and molecular biology over the past 25 years have greatly improved the speed at which this pathogen is detected. Nonetheless, food and environmental samples possess a distinctive set of challenges for these newer, more rapid methodologies. Furthermore, more detailed identification and subtyping strategies still rely heavily on the availability of a pure isolate. However, major shifts in DNA sequencing technologies are meeting this challenge by advancing the detection, identification and subtyping of Salmonella towards a culture-independent diagnostic framework. This review will focus on current approaches and state-of-the-art next-generation advances in the detection, identification and subtyping of Salmonella from food and environmental sources.

Actualización en Patología Infecciosa 2015 / Update in Infectious Diseases 2015

La patología infecciosa continúa estando de actualidad en el mundo. La segunda mitad de 2014 un brote de ebolavirus azotó África occidental con implicaciones en el resto del mudo, de hecho, en España se declaró el primer caso importado de esta infección. En los hospitales de todo el mundo emergen brotes de enterobacterias multirresistentes en un momento en el que la OMS llama la atención sobre los limitados recursos, acuñando el término de 'era postantibiotica'. Sin embargo, el ultimo año pasará a la historia de la medicina como aquel en el que se curó la hepatitis C. Continúan estando de actualidad la dificultad en el control epidemiológico de la transmisión del VIH o las estrategias para la profilaxis antivírica o antifúngica en el paciente inmunosuprimido (AU)

Infectious disease remains current worldwide. During the second half of 2014 an outbreak of ebolavirus hit West Africa with implications in the rest of the world. In fact, Spain declared the first imported case of this infection. Multiresistant enterobacteria outbreaks are emerging all around the world in a moment on which WHO draws attention to the limited resources, coining the term 'post antibiotic era'. On the other hand, 2014 went down in history as one in which hepatitis C is cured. Are also current HIV epidemiological control or strategies for antiviral and antifungal prophylaxis in immunocompromised hosts (AU)

Aplicabilidad de las nuevas técnicas de diagnóstico microbiológico; innovación tecnológica / Applicability of new diagnostic techniques in microbiology; technological innovation

En los últimos años se han introducido nuevas técnicas en los laboratorios de microbiología, incluyendo la espectrometría de masas y los sistemas de secuenciación masiva de próxima generación. Estas técnicas, así como la automatización, la microfluídica, la nanotecnología y la informática, han impulsado la innovación en la prevención y el manejo de las enfermedades infecciosas. Esta aproximación es relevante en el proceso de revitalización y consolidación de los Servicios de Microbiología Clínica (AU)

Different new techniques have been introduced in microbiology laboratories during the last years, including mass spectrometry and next generation sequencing. These techniques, in addition to automation, microfludics, nanotechnology and informatics, have impelled innovation in the prevention and management of patients with infectious diseases. These approaches are relevant for revitalization and consolidation Clinical Microbiology laboratories (AU)

Illumination of growth, division and secretion by metabolic labeling of the bacterial cell surface.

The cell surface is the essential interface between a bacterium and its surroundings. Composed primarily of molecules that are not directly genetically encoded, this highly dynamic structure accommodates the basic cellular processes of growth and division as well as the transport of molecules between the cytoplasm and the extracellular milieu. In this review, we describe aspects of bacterial growth, division and secretion that have recently been uncovered by metabolic labeling of the cell envelope. Metabolite derivatives can be used to label a variety of macromolecules, from proteins to non-genetically-encoded glycans and lipids. The embedded metabolite enables precise tracking in time and space, and the versatility of newer chemoselective detection methods offers the ability to execute multiple experiments concurrently. In addition to reviewing the discoveries enabled by metabolic labeling of the bacterial cell envelope, we also discuss the potential of these techniques for translational applications. Finally, we offer some guidelines for implementing this emerging technology.